#pragma once  
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>

#define LINE_SIZE 1024i
#define FLUSH_NOW 1
#define FLUSH_LINE 2
#define FLUSH_FULL 4

struct myFILE 
{
    unsigned int flags;
    int fileno;
    //缓冲区
    char cache[LINE_SIZE];
    int cap;
    int pos;//下次写入的位置
}


myFILE* my_fopen(const char* path,const char* flag)
{
    int flag1 = 0;
    int iscreate = 0;
    mode_t mode = 0666;
    if(strcmp(flag,"r") == 0)
    {
        flag1 = (O_RDONLY);
    }
    else if(strcmp(flag,"w") == 0)
    {
        flag1 = (O_WRONLY | O_CREAT | O_TRUNC);
        iscreate = 1;
    }
    else if(strcmp(flag,"a"))
    {
        flag1 = (O_WRONLY | O_CREAT | O_APPEND);
        iscreate = 1;
    }
    else 
    {

    }
    int fd =0;
    if(iscreate)
        fd = open(path,flag1,mode);
    else 
        fd = open(path,flag1);
    if (fd < 0)
        return NULL;
    myFILE* fp = (myFILE*)malloc(sizeof(myFILE));
    if(!fp) return NULL;

    fp->fileno = fd;
    fp->flags = FLUSH_LINE;

    fp->cap = LINE_SIZE;
    fp->pos = 0;
    return fp;
}

void my_fclose(myFILE* fp)
{

    close(fp->fileno);
    delete fp;
}

void my_fflush(myFILE* fp)
{
    write(fp->fileno,fp->cache,fp->pos);
    fp->pos = 0;
}

ssize_t my_fwrite(myFILE* fp,const char* data,int len)
{
    memcpy(fp->cache+fp->pos,data,len);
    fp->pos += len;

    if((fp->flags&FLUSH_LINE) && fp->cache[fp->pos-1] == '\n')
    {
        my_fflush(fp);
    }
}

//myFILE* fp = my_open();
//my_close(fp);
//
//my_fwrite(fp);
//my_fflush(fp); 
